1. Field of the Invention
The present invention relates generally to personal audio devices, such as headphones, that include adaptive noise cancellation (ANC), and, more specifically, to architectural features of an ANC system in which control of an ANC system serving separate earspeakers is coordinated between channels.
2. Background of the Invention
Wireless telephones, such as mobile/cellular telephones, cordless telephones, and other consumer audio devices, such as MP3 players, are in widespread use. Performance of such devices with respect to intelligibility can be improved by providing noise canceling using a reference microphone to measure ambient acoustic events and then using signal processing to insert an anti-noise signal into the output of the device to cancel the ambient acoustic events.
Since the acoustic environment around personal audio devices, such as wireless telephones and earspeakers, can change dramatically, depending on the sources of noise that are present and the position of the devices themselves, it is desirable to adapt the noise canceling to take into account such environmental changes.
Therefore, it would be desirable to provide a personal audio system including earspeakers that provides noise cancellation in a variable acoustic environment.